A red weather warning has been issued in Barcelona, where extreme flooding has already begun on the outskirts of the city. 

The threat of potential rain in Barcelona has been elevated to a red alert as the death toll in Valencia, just south of Barcelona, has reached 217 people.

Mobile phones across Barcelona received a message forecasting "extreme and continued rainfall" on the southern outskirts of the city.

"Do not travel unless strictly necessary," Barcelona's population of eight million people were told.

Footage on social media shows heavy rainfall overwhelming stairwells and covering streets with water.

Flights are being diverted from Barcelona city's airport and regional train services have been closed.

#URGENTE: Images from Barcelona's El Prat Airport. Many flights are being diverted to other destinations. ?? #DANA pic.twitter.com/MGUzMSCQOW

— Weather monitor (@Weathermonitors) November 4, 2024

The flash flooding began in Valencia on Tuesday.

In Valencia, divers are searching a flooded underground car park near Valencia's biggest shopping centre, where dozens of people are feared dead.

Locals say they could hear cars colliding from under the rising flood waters.

Berit, who lives in Valencia, said people were afraid to help those stuck in case they were also swept away.

“People going up on the rooftops and shouting for help and you feel, you feel like very you don't know what to do, because you can't really do anything,” she said.

A man walks inside a flood damaged cemetery on the outskirts of Valencia, Spain. 01/11/2024 Image: Associated Press / Alamy Stock Photo